1. Field of the Invention
The present invention relates to a member for electrophotography, a fixing device, and an electrophotographic image forming apparatus.
2. Description of the Related Art
A heat fixing system has been generally employed in an electrophotographic apparatus. That is, a recording material holding an image formed with unfixed toner is introduced into a nip between a fixing member and a pressurizing member placed opposite to the fixing member in a fixing device. Then, in the nip, the toner is heated and pressurized to melt, and the molten toner is fixed onto the recording material.
In this connection, a member obtained as described below has been known as the fixing member or the pressurizing member (hereinafter referred to as “fixing member or the like”). An elastic layer containing a silicone rubber formed of a cured product of an addition-curing-type organopolysiloxane mixture and a surface layer formed by melting fluorine resin powder are placed on a substrate.
It should be noted that the silicone rubber formed of the cured product of the addition-curing-type organopolysiloxane mixture is hereinafter sometimes referred to as “cured silicone rubber.” In addition, the elastic layer containing the cured silicone rubber is hereinafter sometimes referred to as “cured silicone rubber elastic layer.”
The surface layer of each of the fixing member or the like having such configuration can be made thin. Accordingly, in the fixing member with which the unfixed toner image is brought into contact, by virtue of excellent elasticity of the cured silicone rubber elastic layer, the unfixed toner on the recording material can be enclosed and melt without being excessively squashed. Accordingly, shift and blur of an electrophotographic image caused by the excessive squash of the unfixed toner upon fixation can be suppressed. In addition, occurrence of melting unevenness of the toner can be suppressed because the fixing member can follow irregularities of fibers of paper as the recording material well. Further, in the case of a color electrophotographic apparatus, color mixability of multiple color toners on the recording material can be improved.
In this case, as disclosed in Japanese Patent Application Laid-Open No. H08-328418, Japanese Patent Application Laid-Open No. 2005-49382 and Japanese Patent No. 4012744, a heating step at a temperature of 300° C. to 350° C. (hereinafter, the step is referred to as “baking”) is generally needed for melting the fluorine resin powder on the cured silicone rubber elastic layer.